Sealing device



' July 2, 1957 c. M. M CHESNEY- SEALING DEVICE 6 Sheets-Sheet 1 Filed Jan. 16. 1952 aab If I

laillll lul July 2, 1957 c. M. M cHEsNEY 2,797,714

SEALING DEVICE Filed Jan. 16, 1952 6 Sheets-Sheet 3 f I M130. 5 62a J23 $5222 CheaZErflMcC/fi July 2, 1957 c. M. M ccHEsNEY 2,797,714

SEALING DEVICE Filed Jan. 16, 1952 e Sheets-Sheet 4 1/3. lljfia g J90 fig laa ial I I I l 132 133 25:1 69a (9 a United States Patent l SEALING DEVICE Chester M. MacChesney, Chicago, 111., assignor to Acme Steel Company, Chicago, 11]., a corporation of Illinois Application January 16, 1952, Serial No. 266,754

1 Claim. (Cl. 140-932) This invention relates to improvements in sealing devices for use in uniting the ends of a metallic strap by means of a seal. The device of the present invention is particularly adapted for use in operating upon the seal and forming the sealed joint which are described and claimed in my copending application Serial No. 266,753, filed January 16, 1952, now Patent No. 2,759,233. In said copending application there is disclosed a metal seal in the form of a flat plate having one or more-sets of upwardly extending cars which are adapted to be bent downwardly over one or more ends of a metal strap for the purpose of deforming the strap ends and effecting an interlocking connection therewith, and the principal object of the present invention is to provide an improved device for operating upon the seal described in said application and bending the parts thereof into said interlocking engagement. A further object of the invention is to provide a sealing device which may be employed to elfect an interlocking engagement between a metal seal and one or more ends of a strap and also to sever one end portion of the strap from the source of supply. A further object of the invention is to provide a sealing device having a part adapted to coperate with a part of the seal for shearing the strap and separating a portion thereof from the source of supply. Still another object of the invention is to provide a sealing device having a reciprocating plunger adapted to engage the projecting ears of a seal and press them into interlocking engagement with the strap. A further object of the invention is to provide an improved sealing device in combination with improved means for holding a strap end while the strap is being drawn taut around the package. Still another object of the invention is to provide an improved sealing device in combination with a stretching device whereby the strap may be drawn taut around the package while one end thereof is held stationary. Other objects relate to various features of construction and arrangement which will appear more fully hereinafter.

The nature of the invention will be understood from the following specification taken with the accompanying drawings, in which certain embodiments of the invention are illustrated. In the drawings,

Fig. 1 shows a side elevation of a portion of a package having applied thereto one form of the sealing device of the present invention and illustrating one means ofdrawing the strap taut around the package;

Fig. 2 shows an enlarged side elevation of the sealing device illustrated in Fig. l with a portion of the casing thereof removed;

Fig. 3 shows a vertical section on the line 3-3 of Fig. 2;

Fig. 4 is a view similar to that of Fig. 2 showing the plunger of the device depressed by a lateral movement of the operating handle;

Fig. 5 is a detail section on the line 5-5 of Fig. 4;

Fig. 6 shows a top plan view of a form of seal adapted to be used with the sealing device illustrated in Figs. 1 to 5, inclusive;

2,797,714 Patented July 2, 1957 Fig. 7 is a longitudinal section on the line 7-7 of Fig. 6, showing the method of applying one end of the strap to the seal preliminary to passing the strap around the package;

Fig. 8 is a partial longitudinal vertical section on the line 8-8 of Fig. 3, showing the strap and seal in position within the sealing device before depressing the plunger to bend the ears of the seal into interlocking engagement with the strap;

' Fig. 9 shows a longitudinal section through a seal and strap showing the relative positions of the parts after a locking joint has been formed by the operation of the sealing device;

Fig. 10 shows a top plan view, on a smaller scale, of the sealed joint shown in Fig. 9;

Fig. 11 shows a side elevation of a modified form of the invention which comprises a strap stretching device and which is adapted for use on a modified form of seal, portions of the casings of the sealing device and stretching devicebeing removed;

Fig. 12 shows a top plan view of the device illustrated in Fig. 11;

Fig. 13 shows a longitudinal section on the irregular line 13-13 of Fig. 11;

Fig. 14 shows a side elevation of the upper portion of a package having a strap passed around it and showing the relative positions of the parts after the strap stretching device has been operated to draw the strap taut preliminary to depressing the plunger of the sealing device for forming an interlocking joint between the ears of the seal and the strap and cutting off the strap from the source of Fig. 17 shows a top plan view of a form of seal adapted to be used with the form of sealing device shown in Figs. 11 to 16, inclusive;

Fig. 18 shows an end elevation of the form of seal illustrated in Fig. 17;

Fig. 19 shows an enlarged longitudinal section through the upper part of the sealing device illustrated in Fig. 11, showing the position of the seal and strap end preliminary to the employment of the upper end of the plunger for uniting the seal with this strap end;

Fig. 20 is a horizontal section taken on the line 20-20 of Fig. 19, showing a top plan view of the seal and strap end after one set of ears of the seal have been pressed to form an interlocking engagement with the strap end;

Fig. 21 is a partial longitudinal section on the line 21-21 of Fig. 15, showing the seal and united strap end in position within the sealing device with the supply end of the strap in position above the seal preliminary to the depression of the plunger for the purpose of severing the strap from the source of supply and uniting this end of the strap with the seal;

Fig. 22 shows a top plan view of the completed seal joint after the plunger has been depressed to sever the strap from the source of supply and unite the supply end of the strap with the seal;

Fig. 23 is a longitudinal section through the seal on the line 23-23 of Fig. 22;

Fig. 24 shows a top plan view of a third form of the invention which is adapted to be used in connection with another form of seal whereby the seal is united with both ends of the strap, and the strap is cut ofi from the source of supply, by a single operation of the plunger;

Fig. 25 shows a side elevation of the apparatus illustrated in Fig. 24 with a portion of the casing of the stretching device removed;

Fig. 26 is a horizontal section taken on the irregular line 2626 of Fig. 25;

Fig. 27 shOWs a side elevation of the sealing device illustrated in Fig. 25 applied to a package around which a straphas been placed and drawn taut preliminary to the operation of the plunger for the purpose of severing the strap from the. source of supply and uniting both ends of the strap with the seal;

Fig. 28 is a vertical section taken on the line 28,-.28 of Fig. 25;

Fig. 29 is ,a detail section taken on the line 2929 of Fig. 25

Fig. 30 shows a top plan view of a form ofseal adapted to be employed Wi-ththe sealing device illustrated inl igs. 2410 29, inclusive;

Fig. 31 isa sectional view taken on theline 31-31 of Fig. 30; I

Fig. 32 is a sectional view taken on the line 32..32 of Fig. 30;

Fig. 33 shows anenlarged longitudinal section through the sealing device on the'li-ne 33-33 of Fig. 28, showing the seal and strap ends in position within the sealingformed thereon to receive the end of a relatively fixed supporting rod 42. This rod is mounted to swing about a vertical pivot 43 carried by a bracket 44 and this bracket is in turn mounted to swing about a horizontal supporting pin 45 so that the casing 40 may be swung either horizontally or vertically and moved into a position wherein the base plate 46 of the casing may be caused to rest upon a package 47 around which a somewhat flexible metallic strap 48 is adapted to be passed.

The base plate 46 of the device is elongated beyond the one end of the casing as shown in Fig. 2, and the casing is provided above the base plate with a longitudinal recess 49 adapted to receive the seal and the ends of the strap which are adapted to be united to the seal. This recess is provided at one end with an end wall 59 having a slot 51 therein of suflicient size to permit the strap to be passed therethrough While at the same time providing shoulders on the end wall around the slot which are adapted to engage the seal. This end wall has an outwardly projecting flange 50a above the plane of the slot 51 and another outwardly extending flange 50b below the plane of the slot. The adjacent edges of these flanges diverge outwardly so that they provide a guide for the strap which is to be inserted into engagement with the slot 51.

The casing 40 is provided above the recess 49 with a vertical guideway 52 in which is mounted a plunger 53. The plunger is retained in place in its guideway by the front wall 54 of the casing which is secured to the body of the casing by screws 55. two parts 53a and 53b which are secured together by screws 56. The upper part of the plunger is engaged by a transversely extending pin 57 which is pivotally en-' gaged by a link 58. This link is in turn pivotally connected by a pin 59 to the transversely disposed arm 60a of a lever 60 having a bifurcated upper extremity provided with a handle 61. The lever 64) is pivoted on a pin 62 secured in the upper part of the casing 44 and due to the angular arrangement of the part 60a of the lever, the movement of the lever to swing the part 60a from the position shown by full lines in Fig. 2 to the position shown by dotted lines at 6% will first depress the plunger The plunger is formed in '53 and then elevate it. The lower part of the plunger is provided adjacent the end wall 50 with a relatively fixed cutting blade 63 having a beveled cutting edge 63a which projects below the lower flat face of the plunger. Immediately below this cutting blade, the lower wall 46 of the casing is provided with a recess 46a for the purpose of accommodating a projection on the seal hereinafter described.

The device illustrated in Figs. 1 to 5, inclusive, is adapted to be used with the form of seal shown in Figs. 6 and 7. This seal comprises a flat metal plate 65 of rectangular form having a downwardly inclined lip 66 adjacent one end thereof, this lip being formed by cutting the metal of the plate transversely and longitudinally and then bending the tongue downwardly, thus forming a transverse slot 67 adjacent the tongue. At a point inwardly from the tongue 66, the plate 65 is provided with a rectangular slot 68, one edge 68a of which is adapted to form a shearing die against which the metal strap is cut ofi? from the source of supply by the action of the cutting blade 63 previously described. On'the remaining portion of the plate 65, there are formed two pairs of oppositely disposed ears 69; These ears areformed by cutting the metal plate along curved lines 70, removing a portion of the metal along these curved lines and then bending the resulting metal tongues upwardly to form the cars 69. The ears of each pair are spaced apart a distance slightly greater than the width of the strap 48 and they have a normal inward curvature toward each other so that when their upper ends are engaged by the plunger 63, as hereinafter described, they will bend downwardly and inwardly over the strap.

The first step in the operation of using the seal is to passv it into engagement with the free end of the strap 48 and this is accomplished by inserting the strap through the slot 67, above the lip 66, in the inclined position shown at '71 in Fig. 7. The end portions of the strap are then bent into substantially parallel relation with the seal so that the end 48a of the strap underlies the seal and has an interlocking engagement with the lip 66, as shown in Fig. 7. The strap and seal are then inserted edgewise into the recess 49 with the strap engaging the slot 51. The end of the seal will then abut against the end wall 50 and be held against movement. The strap 48 is then looped around the package 47 and the supply end portion thereof is brought up over the base plate 46 and inserted in the recess 49 and slot 51, overlying the seal and the end portion 48a of the strap, as shown particularly in Fig. 8, with the portion 48b lying between the opposite ears 69 of the seal. The down-turned portion of the strap which is bent around the lip 66 will then occupy the recess 46a which is formed in the base plate. The parts are then in position for drawing the strap taut around the package and this may be effected by means of a stretching tool, a portion of which is conveniently illustrated as comprising a head 73 adapted to be moved parallel to the rod 42 by means of a member 74. The head 73 has a base fiange-73a which underlies the strap and a gripping dog 75 engages the upper side of the strap for holding it in fixed position with respect to the head. This gripping dog is pivoted on the head by means of a pin 76 and it has a lower serrated surface 75a adapted to engage the upper side of the strap. A spring 77 is inserted, between the gripping dog and a lug 73b carried by the head for the purpose of moving the gripping dog normally into engagement with the strap. The gripping dog is inclined away from the sealing device so that when the head 73 is moved toward the right, as viewed in Fig. 1, the dog tends to increase its grip on the strap automatically. When the strap has been drawn sufficiently taut around the package by a relative movement of the head 73 and the casing 40, the operator engages the handle 61 and moves the lever 60 toward the left from the position shown in Fig. 2, thereby depressing the plunger 53. As the plunger moves downwardly, the

lower face thereof engages the ears 69 and presses them downwardly until, in the lowermost position of the plunger shown in Fig. 4, the ears have depressed portions of the metal of the end portion 48b of the strap into the recesses in the plate 65 formed by the cutting of the ears, thus effecting an interlocking connection between the end portion 48b of the strap and the seal. As the final depression of the ears 69 takes place, the cutting blade 63 shears oif the strap 48 against the cutting die 6811 which is formed as a part of the seal, so that the strap is cut oif from the source of supply at the same time that the ears are depressed. Due to the shape of the cutting blade 63, the extreme end of the strap is bent downwardly as shown at 48c into engagement with the recess 68 so that this end will not engage objects adjacent to the surface of the package. This completes the formation of the joint and the sealing device may then be moved laterally about the pivot 43 in order to slide the base plate from its position beneath the strap. Sufficient tension will have been created in the strap by the stretching operation to cause it to snap downwardly on the surface of the package when the base plate of the sealing device is removed.

The form of sealing device shown in Figs. 11 to 16, inclusive, is one adapted for use with a form of seal having two sets of cars adapted to be pressed into interlocking engagement with the strap ends. The plunger of the device is first moved in one direction to press one set of ears into interlocking engagement with one end of the strap and then the seal is inserted into another part of the device and, after passing the strap around the package and drawing it taut, the plunger is moved in the opposite direction to press the other set of cars into interlocking engagement with the other end of the strap and at'the same time cut oil? the strap from the source of supply. In this form of the invention, the sealing device 80 comprises a casing 81 having a base plate 82 adapted to rest upon the surface of the package 83 about which the metal strap 84 is adapted to be passed. The casing 81 is provided above the base plate 82 with an inwardly extending recess 85 into which the strap and seal are adapted to be inserted from one side of the device. The base plate 82 extends beyond the body portion of the casing at the right end thereof, as viewed in Fig. 11, and the extremity of the base plate is provided with an upwardly projecting end wall 86 having a horizontally extending slot 87 projecting inwardly from the side thereof to receive the strap which passes through the recess 85.

' The casing 81 is provided with a vertical guideway 88 in which is mounted a plunger 89 of rectangular form. The guideway 88 is open at its upper end and the. upper end of the plunger 89 is adapted to support a seal during the preliminary operation of limiting the seal with one end of the strap by bending one set of ears into interlocking engagement with the strap. For this purpose, the upper end of the plunger 89 is provided at one end with two spaced lugs 89a and 8% which are adapted to receive between them the end of the metal strap and which are adapted to form abutments against which one end of the seal is seated. When the plunger is moved upwardly, the ears of the seal are adapted to be pressed against the overhanging top wall 90 of the casing. The outer lug 89a is preferably of lesser height than the inner lug 89b to facilitate the insertion and removal of the strap from its position between the lugs. The plunger 89 is held in its guideway 88 by the front wall 91 of the casing which is secured to the body portion thereof by screws 92. The vertical movement of the plunger in this guideway is effected by means of an eccentric 93 which is formed on a shaft 94. The sleeve 95 is secured on the eccentric to form a part thereof and this sleeve is journaled in-a bearing 96 which is formed in, thelplunger .89 so that when the shaft 94 is turned about its bearings 96a formed in the walls of the casing,

the rotation of the eccentric efiects a vertical movement of the plunger. The rotation of the shaft 94 is brought about by a lever 97 which is secured on the rear end thereof and which has an enlarged handle 98. The lower end of the plunger is provided with a cutting blade. 99 held in place by a block 100 within a recess in the plunger. edge which is adapted to engage the strap and the lower base plate of the casing is provided with a recess 82a in registry with this cutting blade in order to facilitate the shearing operation hereinafter described.

The casing 81 has formed integrally therewith and extending longitudinally therefrom a rack bar 101 having rack teeth 101a on the upper side thereof and this rack bar is adapted to function as a part of a strap stretching attachment comprising a casing 102 by which the operating parts are carried. This casing has its lower part slidably mounted on the rack bar 101. The casing 102 has a removable rear wall 103 which is secured in place by screws 104. A shaft 105 is formed integrally with the forward wall and is secured to the rear wall by a screw 106 engaging the end thereof. This shaft 105 has journaled thereon a gear wheel 107 having teeth which mesh with the rack teeth 101a. The gear wheel 107 has an elongated hub 107a upon which is mounted a ratchet wheel 108 having ratchet teeth 108a. This ratchet wheel is secured to the gear wheel to rotate therewith and the ratchet wheel is adapted to be rotated to effect a corresponding movement of the gear wheel and thereby effect a movement of the casing longitudinally of the rack bar.

The casing 102 has a longitudinally extending relatively fixed handle 110 having an upwardly extending lug 110a to limit the forward position of the hand of the operator. Beneath the handle 110 and projecting through a vertical slot in the end of the casing, there is a relatively movable handle or lever 111 which is pivoted on a pin 112 extending between the side walls of the casing and which has a lug 111a formed thereon to engage the under side of the handle 110 and thereby limit its upward movement. The lever 111 has an angularly disposed part 111b provided with a lug 1110 which is adapted to engage the top wall of the casing 102 for the purpose of limiting the downward movement of the lever or handle 111. Upon the outer end of the lever arm 111b, there is pivotally mounted a pawl 113 having an extremity 113a which is adapted to engage the ratchet teeth 108a. A detent 114 is pivotally mounted within the casing and has a tooth 114a adapted to engage the ratchet teeth for holding the ratchet wheel against rotation. A coil spring 115 extends between the upper side of the pawl and the lug 1131: which is formed on the upper end of the pawl. This spring is held in place by a pin 116 which engages a recess in the upper side of the detent and which passes through an aperture formed in the part 113b of the pawl. This spring acts normally to force both the detent and the pawl into engagement with the teeth of the ratchet wheel. In order to disengage both the pawl and the detent from the ratchet wheel, the casing 102 is provided with a member 117 which is rotatably mounted in the wall of the casing and which carries a thumb-operated handle 118 on the outer side of the casing. Within the casing the member 117 has one arm 117a to engage the pawl and another arm 117b to engage the detent and by pressing downwardly on the handle 118, the arms 117a and 117b may be turned to move both the pawl and the detent out of engagement with the ratchet wheel against the compression of the spring 115. By a reciprocating movement of the handle 111 with respect to the handle 110, an intermittent rotary motion may be imparted through the pawl to the ratchet wheel 108 and the corresponding movement of the gear wheel 107 will move the casing 102 longitudinally of the rack bar 101. When the end of the rack bar has been reached, a reverse movement may be effected by pressing on the handle 118 to re lease the ratchet Wheel from the pawl and detent where The lower end of the knife has a beveled.

upon the casing102 may be, moved freely toward the. left, as viewed in Fig. 11;

Withoneend' of the strap held stationary with respect to the casing81', the relative movement of the. casing 102 is utilized for the purpose of stretching the, strap through. a connection of the last-mentioned casing with the other end of the strap. For this purpose, the casing 102 is providedwith an upwardly. extendingbaseplate 120, on which the strap is adaptedto. seat. Above this base plate there. is mounted a gripping dog121' which is. pivoted on. a pin. 122 secured to thecasing 1.02". The gripping dog 121 is provided at one endwith a curved surface 121a, concentric. with the axis of the pin 122, which bears against. the curved flange 123 which. is formed on the casing, and at the'other end the gripping dog is provided with a serrated gripping surface 1215 which is adapted to contact with the upper side of the strap. A coil spring 124 engages a.recess. in theupper inclined surface of the gripping. dog 12 1 and bears at its upper end'on a lug 125 projecting from the casing, sothat. this spring normally forces this gripping dog downwardly toward the flange 120. Due to the inclination of the. gripping dog downwardly and awayfrom the casing 81, the. movement of the casing 1*02toward' the right, as viewed inv Fig. 11, is adapted to increase the grip of the dog upon the strap while a movement of the casing 102 in the opposite direction will automatically release thedog from engagement with the strap. For the purpose of further facilitatingthe release of the strap by the gripping dog after the stretching operation has been completed, the casing 81, is provided with an arm 128 projecting longitudinally therefrom in the path of movement of the gripping dog 121 so that when the casing 102 is moved into. a position relatively close to thecasing 81, the arm 128 engages the dog 121 and'moves the dog'upwardly away from the flange 120.

A form of seal with which the device illustrated in Figs. 11 to 16, inclusive, is adapted to be used, is shown in Figs. 17 and 18; This seal comprises a rectangular metal plate 130 having at one end two pairs of upwardly extending ears 131 and at the other end two other'pairs of upwardly extending ears 132. Between these ears, the plate isprovided with a transverse rectangular slot 133, one edge 133a of which is adapted to serve as a shearing die against which the strap is cut off by the coaction of the cutting blade 99 previously referred to. The cars 131 are formed by cutting the metal of the plate along circular lines and removing; segments of metal of circular contour, thereby leaving tongues having curved edges which are then bent upwardly to form the ears having the shape shown in Fig. 18-, where the ears of each pair are illustrated as being curved upwardly and inwardly toward each other. This leaves apertures 134 in the plate beneath the ears and the similar formation of the ears 132 leaves other similar apertures 135 beneath those ears. The two ends of the strap are adapted to be inserted, respectively, between the ears of each set and' then these ears are bent downwardly to project the metal of the strap into the openings 134 and 135;

In the operation of using the sealing device shown in Figs. 11 to 16, inclusive, with the formof seal shown in Figs; l7'and 18; the first step is to unite the free end of the strap with the seal and this is done by placing the plate 130 of the seal on the upper end of the plunger 89 and then-placing the free end of the strap between the pairs of ears 131, as shown in Fig. 19. The handle 98 is then'moved toward the right as viewed'in Figs. 11 and 14, to. elevate the plunger by the rotation of the eccentric 93.. The. elevation of the plunger forces the ears 131 against. the under side of the top wall 90 of the casing and:theseearsare thus depressed over the strap and force portionsof the strap into the openings 134 in the seal with the result that an interlocking joint is formed between the seal and the free end of the strap. The next step is tobring the base plate 82 of the sealing device intoengagement with the surface of the package83, as. shown in Fig. 14; and to place the sealin the recess with the end of the seal abuttingagainst'the end wall 86 and with the strap passing through the slot 8 7.v Thisv end portion of; the strap is placed beneath the, flange of the stretching-apparatus and is passed around the package 83. The supply'end of the strap is then brought up around the other, side of the package and is' placed within therecess 85- between the opposite ears 132' and with the strap extending also through the slot 87 above the end'portion 84a of the strap which has previously been attached to the. seal. This supply end of the strap is then inserted beneath thev gripping dog 121i and the parts are then inv readiness, for drawing the strap tautaround the package.

The end 84a of the strapis thenheld against movement. by its abutment; against the endwall 86 of the. casing Sland the supply'end of: the strap is gripped by the dog 121, so that when the lever'arm 111, is reciprocated to effect movement of thecasing 102 toward the right, as viewed" in Fig. 14, the end portion 84b of' the strap slides over the seal and through. the slot 87 until the strap is intight engagement with the package. When sufficient tension has been set up in the strap 84; thehandle. 98 and lever 97 arethrown from. the position shown. by

full lines in Fig. 14 to the position shown by dotted lines. at 97a, thus moving the plunger 89 downwardly with the.

wherein ,the two ends.84a and84b are held'in interlocking engagement with the seal by. the ears 131; and 132, respectively, while the. extremity 8.40 of the strap has been forced downwardly intothe opening 133'by the beveled cutting edge of the blade. 99. The casing102 may then be moved, toward the left, after depressing the thumb lever 1 18, and when the gripping. dog 121 engages the arm 128. of the strap, the supply portion of the strap will be automatically released.

In Figs. 24 to 29; inclusive, of the drawings there is illustrated another modification of the invention which is adapted to effect an interlocking engagement of the seal with both ends of the strap by a single movement of the plunger.. Inthis form, the sealing device comprises a casing 141. having a base plate 142 adapted to rest upon the surface of the package 143 about which the flat metal strap 144 is passed. Inthe side of the casing 141, there is formed a recess 145 adapted to-receive-the seal and a portion of the strap. At one end of this re cess the casing has an end wall 146 provided, with an inwardly extending horizontal slot 147 through which the strap passes. The sealis adapted to abut against this.

end wall so that it is properly positioned in the recess. The casing is provided with a vertical. guideway 148 in which is-mountedaplunger149. The. guideway is closed on its front side by the front wall 150 which is held in place by the screw 151. The plunger 149 is provided with a circular aperture. in which is journaled the eccentric 152, formed as a part of a shaft 153..

blade 184is. secured in the lower face of the plunger 149 with itsbeveled cutting edge 184a projecting downwardly therefrom. The, lower surfaces 149a and 14911 of the.

plunger, on opposite sides of the cutting blade, are, preferably oifsetfrom each other due to the dilferent thicknesses of material. to be engaged thereby.

Inasmuch as this form of the invention does not provide.

means'for attaching the strap to the seal before. the strap This shaft is journaled inthe. walls of the casing and the rear projecting is passed around the package, other means must be provided for securing one end of the strap in fixed relation to the casing 141 while the strap is being drawn taut around the package and this means must permit the supply end of the strap to have relative movement during the stretching operation. This is effected by providing the projecting portion 142a of the base plate with a recess in which is mounted a gripping member 155 having an upper serrated surface 155a which projects above the surface of the plate to coact with the under side of the strap. Above this gripping member, there is mounted a roller 156 which is arranged to revolve about an eccentric 157 formed as a part of a shaft 158. This shaft is journaled in the wall 159 and arm 16!) which extend longitudinally from the casing and its front wall, respectively, and the forward end of the shaft carries a relatively fixed lever 161 by which it may be rotated. The rear end of the shaft 158 projects beyond the wall 159 and a coil spring 162 is mounted on this projecting portion with the outer end thereof engaging a pin 163 passing transversely through the shaft, thus holding the shaft firmly in place in its bearings. By moving the lever arm 161, the eccentric 157 may be rotated to raise or lower the roller 156 for the purpose of regulating the grip upon the strap, as hereinafter described.

The wall 159 and base plate 142a of the casing 141 are formed integrally with a longitudinally extending rack bar 165 having rack teeth 165a. This rack bar forms a part of a strap stretching attachment comprising a casing 166 which is similar in all respects to the casing 102 previously described. The lower part of this casing is slidably mounted upon the rack bar 165 and the upper part thereof carries a relatively fixed handle 167. Beneath this handle there is a relatively movable handle or lever 168 which is adapted to operate the pawl 169 to rotate the ratchet wheel 170 and thereby rotate the gear 171 which meshes with the teeth of the rack bar. The ratchet wheel is normally held against rotation by a detent 172 and the pawl and the detent are normally held in engagement with the ratchet teeth by the coil spring 173. A member 174, controlled by the thumb lever 175, is adapted to effect the release of the pawl and detent from the ratchet wheel by the action of its arms 174a and 174b, respectively. These parts are similar in construction and operation to the corresponding parts of the form of the invention previously described.

The lower part of the casing 166 is provided with an outwardly projecting plate or flange 175 which is adapted to engage the under side of a. portion of the strap. The upper side of this part of the strap is engaged by the inclined gripping dog 176 which is pivoted on the pin 177. The upper curved end 176a of this gripping dog engages the curved lug 178 formed'on the wall of the casing and the lower end of the gripping dog has a serrated surface 176b adapted to engage the strap. A coil spring 178 normally forces the gripping dog downwardly toward the plate 175. This gripping dog acts like the gripping dog in the form of the invention shown in Fig. 11 in that it tends to increase its grip upon the strap as the casing 166 moves toward the right as viewed in Fig. 25, while it permits the ready release of the strap when the casing is moved in the opposite direction. In order to facilitate the release of the strap by the gripping dog, the dog 176 is provided with a forwardly extending arm 180 which is adapted to engage a projection 181 formed on the lever 161. When the casing 166 is moved toward the left to a position closely adjacent to the casing 141, the arm 180 engages the projection 181, thus elevating the gripping dog 176 and at the same time turning the lever 161 to elevate the roller 156. The strap is thus simultaneously released by both gripping devices.

One form of seal adapted for use with the form of apparatus shown in Figs. 24 to 29, inclusive, is shown in Figs. 30, 31 and 32. This seal is in the form of a flat, rectangular metal plate 185 having at one end thereof two t 10 r 1 1 pairs of cars 186 and at the other end thereof two other pairsof ears 187, with an intervening transverse rectangular slot 188 between the two sets of ears. The cars 186 are formed by cutting the metal plate along semicircular lines, removing semicircular strips of metal along each cut, and then bending upwardly the resulting tongues to form the hook-shaped ears 186 which have their upper portions 186a directed horizontally parallel to the body of the plate and, overlying the apertures 189 which are formed in the plate. -The ears 187 are similarly formed by cutting the metal of the plate along semicircular lines, removing. a portion of the metal adjacent each cut, and bending the resulting tongues upwardly to form the ears 187 but these ears differ from the ears 186 in that they are merely curved inwardly toward each other to a slight degree, as shown in Fig. 31, similar to the ears of the other seals, previously described, with apertures 190 in the plate beneath them.

In the use of the apparatus illustrated in Figs. 24 to 29, inclusive, the seal 185 is first placed in the recess with the end thereof abutting against the wall 146 and the free end 144a of the strap is placed in position beneath the tongues 186 and with its extremity terminating short of the slot 188. The strap 144, which will then extend through the slot 147, is passed beneath the roller 156 and around the package 143, after which the supply end portion 144b of this strap is inserted in the slot 145 between the opposed ears 187 of the seal. This supply end of the strap is then carried on over the ears 186, through the slot 147 and beneath the roller 156 which is then lowered by the rotation of the handle 161 to cause the super imposed layers of the strap to be held against the serrated gripping member 155. The supply end of the strap is then inserted beneath the gripping dog 176 and is drawn taut by reciprocating the lever 168 to cause the casing 166 to move away from the casing 141. During this operation, the free end 144a of the strap is held stationary with respect to the casing 141 by reason of the engagement therewith of the gripping member but the supply portion 144b of the strap slides over the part 144a of the strap and the roller 156 revolves to permit this sliding movement while maintaining sufficient grip to prevent movement of the end 144a on the serrated gripping surface 155a. When the strap 144 has been drawn sufliciently taut around the package, the handle 15411 is thrown from the position shown in Fig. 27 toward the left to rotate the eccentric 152 and thereby lower the plunger 149. As the plunger lowers, the surface 149a thereof engages the ears 187 and bends them downwardly while at the same time the surface 14% of the plunger engages the upper surface of the portion 144]] of the strap and operates therethrough to press the ears 186 downwardly. This results in causing both sets of ears to be pressed into opposite end portions of the strap to force them into interlocking engagement with the apertures 189 and 190 which are formed in the seal. At the same time that this occurs, the cutting blade 184 cooperates with the edge of the aperture 188 in the seal to cut off the end portion 14412 of the strap from the source of supply and to bend the extremity 1440 of the cut-off portion downwardly into the aperture 188. This results in the formation of the completed sealed joint having the form illustrated particularly in Figs. 34 and 35. When the joint has been formed, the handle 154a is thrown toward the right, as viewed in Fig. 25, to elevate the plunger, and the operator then presses on the thumb lever to release the ratchet wheel 170 from the pawl and detent so that the casing 166 may be restored to its initial position adjacent the casing 141. As the casing 166 reaches this position, the arm engages the projection 181 of the lever 161 so that the gripping dog 176 and the roller 156 are simultaneously moved out of engagement with the portion of the strap which has previously been held thereby. A sidewise movement of the sealing device will then remove it from engagement with the strap 144 and the tension in 1 1 the strap will cause it to snap downwardly into close proximity to the surface of the package. Although three forms ofthe invention have been shown and: described by way of illustration, it will be under stoodthat it may be constructed in various other embodimerits coming within the scope of the appended claim.

I claim: A i The combination in a, sealing device of a main casing having a plate adapted to engage a seal which supports a strap, means carried by said main casing'for gripping a portion of said strap, an auxiliary casing mounted for movement with respect to said main casing, a gripping dog mounted on said auxiliary casing for gripping said strap after it has been looped around a package with a portion thereof passing over said seal, operating mechanism for'eifecting movement of said auxiliary casing with respect to said main casing, and means carried by said gripping means and said gripping dog for engaging each other to cause said strap to be released by said gripping means and said gripping dog when said auxiliary casing is moved toward said'main casing.

References Cited in the file of this patent UNITED STATES PATENTS 238,417

Miller Mar. 1, 1881 1,408,846 Turner Mar. 7, 1922 1,505,754 Turner Aug. 19, 1924 1,665,323 Payne Apr. 10, 1928 1,886,046 Rico Nov. 1, 1932 1,924,845 Edwards Aug. 29, 1933 2,040,576 Timrnerbeil May 12, 1936 2,312,400 Govanus Mar. 2, 1943 2,349,608 Bramble May 23, 1944 2,368,969 Cleveland Feb. 6, 1945 2,612,803 McAneny Oct. 7, 1952 FOREIGN PATENTS 482,787 Great Britain Apr. 5, 1938 

